The fear propaganda is a winner. Keep the little people scared and distracted so they don't notice really important issues moving forward. Make the people fear illigal imigration so they don't realize that the loss of jobs is caused by internal forces. Make the people fear nebulous outsiders so they don't realize the loss of freedom as government imposes wet-dream laws they've been wishing for but could never put in place in the past.

Sadly, this is a frequent and powerful tool for manipulating a populace; it's not unique to US governance.